try_compile: Don't accept try_run arguments

Modify cmCoreTryCompile to only recognize try_run arguments when
actually parsing try_run. (The old behavior was to recognize try_run
arguments for try_compile also and then complain.)

This has a small chance that a try_run keyword will be consumed as part
of a multi-valued keyword argument. However, this behavior is more
consistent with other commands, as we don't normally treat keywords as
universally reserved. Also, the code is noticeably simplified.

2 files changed, 19 insertions, 34 deletions

diff --git a/Source/cmCoreTryCompile.cxx b/Source/cmCoreTryCompile.cxx
index 46ee8db..7b9dc2e 100644
--- a/Source/cmCoreTryCompile.cxx
+++ b/Source/cmCoreTryCompile.cxx
@@ -145,6 +145,10 @@ auto const TryCompileArgParser =
     .BIND_LANG_PROPS(HIP)
     .BIND_LANG_PROPS(OBJC)
     .BIND_LANG_PROPS(OBJCXX)
+  /* keep semicolon on own line */;
+
+auto const TryRunArgParser =
+  cmArgumentParser<Arguments>{ TryCompileArgParser }
     .Bind("COMPILE_OUTPUT_VARIABLE"_s, &Arguments::CompileOutputVariable)
     .Bind("RUN_OUTPUT_VARIABLE"_s, &Arguments::RunOutputVariable)
     .Bind("RUN_OUTPUT_STDOUT_VARIABLE"_s, &Arguments::RunOutputStdOutVariable)
@@ -160,7 +164,8 @@ Arguments cmCoreTryCompile::ParseArgs(
   cmRange<std::vector<std::string>::const_iterator> args, bool isTryRun)
 {
   std::vector<std::string> unparsedArguments;
-  auto arguments = TryCompileArgParser.Parse(args, &unparsedArguments, 0);
+  const auto& parser = (isTryRun ? TryRunArgParser : TryCompileArgParser);
+  auto arguments = parser.Parse(args, &unparsedArguments, 0);
   if (!arguments.MaybeReportError(*(this->Makefile)) &&
       !unparsedArguments.empty()) {
     std::string m = "Unknown arguments:";
@@ -194,31 +199,6 @@ Arguments cmCoreTryCompile::ParseArgs(
         arguments.RunWorkingDirectory->empty()) {
       arguments.RunWorkingDirectory = cm::nullopt;
     }
-  } else {
-    std::string tryRunArgs;
-    if (arguments.CompileOutputVariable) {
-      tryRunArgs = cmStrCat(tryRunArgs, "  COMPILE_OUTPUT_VARIABLE\n");
-    }
-    if (arguments.RunOutputVariable) {
-      tryRunArgs = cmStrCat(tryRunArgs, "  RUN_OUTPUT_VARIABLE\n");
-    }
-    if (arguments.RunOutputStdOutVariable) {
-      tryRunArgs = cmStrCat(tryRunArgs, "  RUN_OUTPUT_STDOUT_VARIABLE\n");
-    }
-    if (arguments.RunOutputStdErrVariable) {
-      tryRunArgs = cmStrCat(tryRunArgs, "  RUN_OUTPUT_STDERR_VARIABLE\n");
-    }
-    if (arguments.RunWorkingDirectory) {
-      tryRunArgs = cmStrCat(tryRunArgs, "  WORKING_DIRECTORY\n");
-    }
-    if (arguments.RunArgs) {
-      tryRunArgs = cmStrCat(tryRunArgs, "  ARGS\n");
-    }
-    if (!tryRunArgs.empty()) {
-      this->Makefile->IssueMessage(
-        MessageType::AUTHOR_WARNING,
-        cmStrCat("Ignoring try_run arguments for try_compile:\n", tryRunArgs));
-    }
   }
   return arguments;
 }
diff --git a/Tests/RunCMake/try_compile/TryRunArgs-stderr.txt b/Tests/RunCMake/try_compile/TryRunArgs-stderr.txt
index 717c208..2a58e71 100644
--- a/Tests/RunCMake/try_compile/TryRunArgs-stderr.txt
+++ b/Tests/RunCMake/try_compile/TryRunArgs-stderr.txt
@@ -1,13 +1,18 @@
 ^CMake Warning \(dev\) at TryRunArgs.cmake:[0-9]+ \(try_compile\):
-  Ignoring try_run arguments for try_compile:
-
-    COMPILE_OUTPUT_VARIABLE
-    RUN_OUTPUT_VARIABLE
-    RUN_OUTPUT_STDOUT_VARIABLE
-    RUN_OUTPUT_STDERR_VARIABLE
-    WORKING_DIRECTORY
-    ARGS
+  Unknown arguments:
 
+    "COMPILE_OUTPUT_VARIABLE"
+    "compOutputVar"
+    "RUN_OUTPUT_VARIABLE"
+    "runOutputVar"
+    "RUN_OUTPUT_STDOUT_VARIABLE"
+    "runOutputStdOutVar"
+    "RUN_OUTPUT_STDERR_VARIABLE"
+    "runOutputStdErrVar"
+    "WORKING_DIRECTORY"
+    "runWorkDir"
+    "ARGS"
+    "runArgs"
 Call Stack \(most recent call first\):
   CMakeLists.txt:[0-9]+ \(include\)
 This warning is for project developers.  Use -Wno-dev to suppress it.$